(a) The city shall not have power to sell, lease or dispose of any real estate unless:
(1) The resolution authorizing the sale, lease or disposal thereof shall be completed in the manner in which it is to be finally passed and has remained on file with the Clerk for public inspection for twenty-eight (28) days before the final adoption or passage thereof, with notice of intent to sell, lease or dispose of such property published not less than fifteen (15) days before the Council finally acts thereon, and unless
(2) Such action is approved by.the affirmative roll call vote of five (5) or more members of the Council.
(b) No contract shall be made with any person who is in default to the city.
(c) No exclusive contract shall be made with any person except for the normal purchasing of supplies and equipment, the making and acquisition of public improvements, and such as may be authorized by this charter.
(d) No extra compensation shall be paid to any public officer, agent, employee or contractor after the service has been rendered or the contract entered into.
(e) No contract shall be amended after it has been made, except upon authority of five (5) or more members of the Council.